Axial airgap electric rotary device



June 1955 J. HENRY-BAUDOT 3,189,773

AXIAL AIRGAP ELECTRIC ROTARY DEVICE Filed March 3, 1961 7 A, I II a. 2 7// H F n LV/ 4 A I o v a 5 4 United States Patent 3,189,773 AXIAL AIRGAP ELECTRIC ROTARY DEVICE Jacques Henry-Baudot, Antony, France, assignor to Printed Motors Inc., New York, N.Y. Filed Mar. 3, 1961, Ser. No. 93,188 Claims priority, application France, Mar. 10, 1960, 821,154, Patent 1,259,057 11 Claims. (Cl. 310-268) The present invention concerns improvements in or relating to axial airgap electric rotary machines of the kind wherein the armature includes a winding made of flat conductons intimately adhering to insulated faces of an annular carrier member over which said conductors are distributed in two sets of half-turns and from which the corn plete pattern of the winding is obtained by face-,to-face connections between the ends of the halfturn conductors.

One object of the invention is to provide an arrangement of such rotary machine which is specially suitable for driving a cylindrical cage-shaped member such, for

instance, as a wheel, a pulley or a drum.

According to a feature of the invention, the said cage member is actually embodied in the electric rotary machine as a supporting member for the disc-shaped armature, said cage being mounted on bearings carried by sleeves supporting the inductor structure of the machine, which is mounted on a fixed shaft at the axis of the machine.

According to a further feature of the invention, the armature disc member is secured within said cage by the periphery thereof and, more definitely, by the attachment to the rim of the cage of an annular portion of the armature disc which is left free of any winding part thereon for the punpose of making this attachment.

According to :a further feature of the invention, the said armature disc rotates within an airgap defined by a double ring of inductor poles and said double ring is made of U- shaped magnets :aifixed by means of a pair of flanged hubs secured on the fixed shaft at the axis of the machine.

According to a further feature of the invention, in order to facilitate the mounting of said U-shaped magnets, each one of said magnets is made of a radial coaptation or fitting together of at least two elementary magnets so that each magnetic pole is made as a slotted pole along the radial direction thereof.

According to a further feature of the invention, a number of guiding thrust members are provided on the stator part of the machine for hearing against opposite faces of an annular portion of the armature disc near its inner periphery, the brushes of the machine being arranged to act as part of said thrusts.

For detailing these and further objects and features of the invention, reference is made to the accompanying drawings, wherein:

FIG. 1 shows an elevation View and FIG. 2, a crosssection view of an illustrative embodiment according to the invention. FIG. 1 comprises two half-views in crosssection of said elevation, the right-hand one according to line a and the left-hand one according to line b of FIG. 2; and said FIG. 2 also comprises two half-views, the right-hand one according to line 0 and the left-hand view according to line a of FIG. 1.

In said embodiment, the armature disc is fixed and attached by the outer periphery of its insulating carrier 1, over which is formed the double-face winding 2 proper, to a ring 3 provided in the inner wall of a rim 4 of a wheel, pulley or drum. Said attachment is for instance made by bolts or screws such as shown at 5. When the cage is not provided with a rim but made of two end discs spaced apart by bars, an additional ring may be attached to said bars for the attachment of the edge of the armature disc. In the shown example, the rim 4 is ice attached to two circular end plates 6 and 7 each having a central opening.

Said plates are journalled around a fixed shaft 12 by means of bearings 10 and 11 applied on the end sleeves of two flanged hubs 8 and 9 arranged around said shaft and spaced apart by the magnets 13 which they embrace. Rings 14 and 15 threaded on the ends of hubs 8 and 9 clamp the bearings 10 and 11 in place. Once the assembly is effected, pins may be used for attaching the flanged hub 8 and 9 to the shaft.

The hubs 8 and 9 are provided with radial flanges 16 and 17 preferably having depressed sector shaped portions in their radial faces for guiding the U-shaped magnets; Said magnets must be introduced through the central aperture of the armature disc (after said disc has been attached to the rim, one of the hubs, 8 for instance and one of the plates, 6 for instance, having been assembled I but not the other members of the above-defined assembly). The smaller the number of poles in the machine, the greater will be the difficulty to place the magnets in position since the central aperture of the armature disc cannot be made too wide for a given external diameter without affecting the efficiency of the machine. In order to simplify the assembly of the magnets, each pair of poles is made of two U-shaped magnets so machined so as to coacting or fit together within the sector-shaped depressions formed in the radial bases or flanges 16 and 17,

' as shown on FIG. 2, wherein each magnet 13 as shown in FIG. 1 is made of two coactating magnets 13 and 13 On the lefit-hand half-view of FIG. 2, part of a serieswave printed winding of eight poles and forty-one conductors per face is shown. The traces or solid lines delineating the conductors, which are contiguous on the surface, denote spacings between the said conductors. The pattern on the other face of the winding disc is similar to the shown one except that, the inclined portions appear, as seen from the same face of the disc and supposing the member transparent, as oppositely inclined with respect to the shown part of the winding. The

radial and sector-shaped portions of the conductors are in registering relation from face to face. The dots at the ends of the conductors mark the through face-to-face connections. Instead of a series-wave winding, one may use a mesh-type winding. Such kinds of printed-circuit windings are for instance disclosed in co-pending application No. 1,128/ 60, filed January 7, 1960 as a divisional and continuation-impart application of older application No. 691,434, dated October 21, 1957, now Patent No. 3,090,880.

As such "a kind of armature disc, if of sufficiently important dimension, presents a certain risk of deforma tion during the use of the machine, guiding thrusts are further provided for bearing against the faces thereof, and in registering relation by pairs, mainly near the inner edge of the disc. Such thrust, or guiding members, which may include ball or graphite arrangements for reducing the Wear, are for instance carried by the flanges 16 and 17 and are shown at 18 and 19 on the drawing. They pass between the magnetic poles of the machine. Since at least one pair of brushes is necessary in a serieswave winding (as many pairs of brushes as magnetic poles for a mesh-type winding), such brushes may be made part of said pairs of thrusts, as shown for instance at 20 in FIG. 1 wherein a brush bearing on one face of the armature disc is opposed to a mere mechanical guiding member 18.

The proviison of U-shaped magnets enables an increase of efliciency due, for the one part, to the fact that the armature is inserted between a pair of pole rings, and for the other part to the fact that each such magnet may be magnetized up to saturation by inserting a magnetic sheet between the branches of the U-shaped member for such a magnetization, whereafter, said magnetic sheet is withdrawn before the magnet is inserted in machine assembly.

What is claimed is:

1. A rotary electric machine comprising, in combination, a hollow cylindrical member, means mounting said member for rotation about itscylindrical axis, a flat disctype armature mounted within said member with its plane normal to the axis of said member and having a central opening therein, an annular winding carried by said armature between its inner and outer peripheries, means attaching the outer periphery of said armature to said cylindrical member, an annular field structure located within said cylindrical member and mounted upon a fixed support co-axially with said cylindrical member, said field structure comprising two annular portions positioned on opposite sides of the winding of said armature With a small clearance between each annular portion and said armature.

2. A machine according to claim 1 wherein said fixed support for said field structure comprises a shaft extending through said cylindrical member, and the mounting means for said cylindrical member includes apertured end plates secured to the ends of said-member and surrounding end portions of said shaft.

3. A machine according to claim 2 wherein said annular field structure included sleeve portions surrounding said shaft and extending in opposite directions towards said end plates, and bearings surrounding said leeves and supporting said end-plates for rotation about the axis of said sleeves.

4. A machine according to claim 1 wherein said armature comprises a carrier dischaving an outer annular portion located beyond the outer periphery of said winding,

and the mounting means for the armature comprises means securing said outer annular portion of said carrier to said cylindrical member.

5. A machine according to claim 1 wherein said field structure includes a plurality of U-shaped magnets having their yoke portions passing through the central opening of said armature and their pole portions located on opposite sides of said armature, said magnets being distributed in an annular array about the axis of said annular field structure.

6. A machine according to claim 5 wherein said annular field structure includes two circular plates mounted on opposite sides of the annular array of U-shaped magnets, each plate having recesses formed in a radial face thereof for receiving and holding said magnets in proper location in said array.

7. A machine according to claim 6 wherein said cylindrical member is provided with an end-plate with a central opening formed therein, and a fixed shaft extending through said opening and supporting said circular plates of said field structure.

8. A machine according to claim 7 wherein said circular plates have annular hub portions surrounding and secured to said shaft, and annular bearings surrounding said hubs and supporting said cylindrical member for rotation about the axis of said shaft.

9. A machine according to claim 5 wherein each magnet forming opposite poles on opposite sides of said armature is divided into two separate but contacting portions along a radial plane passing through the axis of said annular field structure.

10. A machine according to claim 1 and including a plurality of pairs of thrust members distributed about the axis of said armature, the members of each pair being located on opposite sides of said armature and engaging opposite faces of said armature at aligned points in the inner peripheral portion thereof.

11. A machine according to claim 10 wherein certain of said thrust elements comprises brush elements engaging the winding on said armature.

References Cited by the Examiner UNITED STATES PATENTS 2,430,843 11/47 Colwell 310-268 2,624,856 1/53 Younger 3 1074 2,857,534 10/58 Beach 31074 2,979,238 1/61 Swiggett 310268 3,096,455 7/63 Hahn 310-268 DAVID X. SLINEY, Examiner.

MILTON O. HiRSl-IFIELD, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,189,773 June 15, 1965 Jacques Henry-Baudot appears in the above numbered pat- It is hereby certified that error said Letters Patent should read as ent requiring correction and that the corrected below.

Column 2, line 17, before "plates" insert end line 25, strike out "so", second occurrence; line 26, for "coacting" read coapt line 27, for "bases or" read faces of line 29, for "coactating" read coaptating Signed and sealed this 27th day of December 1966.

( L) Attest:

ERNEST W. SWIDER Attesting Officer Commissioner of Patents EDWARD]. BRENNER 

1. A ROTARY ELECTRIC MACHINE COMPRISING, IN COMBINATION, A HOLLOW CYLINDRICAL MEMBER, MEANS MOUNTING SAID MEMBER FOR ROTATION ABOUT ITS CYLINDRICAL AXIS, A FLAT DISCTYPE ARMATURE MOUNTED WITHIN SAID MEMBER WITH ITS PLANE NORMAL TO THE AXIS OF SAID MEMBER AND HAVING A CENTRAL OPENING THEREIN, AN ANNULAR WINDING CARRIED BY SAID ARMATURE BETWEEN ITS INNER AND OUTER PERIPHERIES, MEANS ATTACHING THE OUTER PERIPHERY OF SAID ARMATURE TO SAID CYLINDRICAL MEMBER, AN ANNULAR FIELD STRUCTURE LOCATED WITHIN SAID CYLINDRICAL MEMBER AND MOUNTED UPON A FIXED SUPPORT CO-AXIALLY WITH SAID CYLINDRICAL MEMBER, SAID FIELD STRUCTURE COMPRISING TWO ANNULAR PORTIONS POSITIONED ON OPPOSITE SIDES OF THE WINDING OF SAID ARMATURE WITH A SMALL CLEARANCE BETWEEN EACH ANNULAR PORTION AND SAID ARMATURE. 